Explosive



Patented Dec. 18, 1928.

UNITED. STATES PATENT 1oF-F|cE.-

ALEXANDER CRUIGKSHANK SCOTT, OF LONDON, ENGLAND, A SSIGNOR '10 MEXCO LIMITED, OF LONDON, ENGLAND, A DRITISH GOMI'ANY.

EXPLOSIVE.

No Drawing. Application filed July 28, 1926, Serial No. 125,586, and in .Great Britain August 12, 1925.

This invention is for improvements in and relating to explosives of the kind in which a salt containing readily available oxygen, e. g. chlorate or perchlorate of potassium or ni-. trate of ammonia (which salt will hereinafter be referred to as the crystals), is first compressed into the form o f a cartridge and subsequently the cartridge is impregnated with a nitro-body, such as nitro-benzene, or a hydro-carbon oil, 'such as kerosene.

Neither nitro-bodies nor hydrocarbon oils" have been found completely satisfactory. If a nitro-body, such as nit-ro-benzene, be employed, this has to be employed in a certain excess in order to overcome the tendency of the nitro-body to become unevenly and incompletely disseminated throughout the mass of crystals and the presence of an excess of nitro-body has the efiect of lowering the energy-density of the char e, that is, the

energy per unit of volume. I on the other hand, a hydrocarbon oil alone be employed, the explosive is diflicult to detonate.

The present invention has for one of its objects to meet the difliculty occasioned by the tendency of nitro-bodies to become evenly disseminated throu hout the mass of crystals, and a further 0 ject is to provide an improved explosive which shall possess a high energy-density and shall, at the same time, be capable of ready detonation.

According to the invention a process for impregnating explosive cartrid es of the kind described w1th a liquid nitroody is characterized by effecting the impregnation of the cartridge by the aid of a liquid-spreading agent (for example kerosene) which agent has the property of assisting the nitro-body to creep over the surfaces of the crystals and thereby to become. evenly disseminated throughout the mass of said crystals, for the purpose of eliminatingor reducing the necessity of employing an excess of nitro-body as aforesaid.

While the preferred spreading agent is kerosene or like hydrocarbon other liquid hydrocarbons can be employed, for example, xylene, but if xylene is employed it is usually desirable to remove it by evaporation from the explosive after the impregnation has been effected.

The nitro-body employed is preferably one which is miscible with the, spreading agent and incorporation can then be efiected by imprcgnatitng a charge of crystals with a mixtureof nitro-body and spreading agent. Alternat vely, and especially where the nitrobody and spreading a ent are not miscible with one another the liquid nitro-body may first be introduced into a chargeof the crystals for example by immersion of the crystals in the nitro-body) and thereafter the spread- The invention includes an explosive car- I tridge of the kind described consisting of a body of crystals having uniformly disseminated throughout their mass after they have been compressed into cartridge form a mixture of liquid nitro-body and a hydrocarbon oil which forms a spreading agent therefor for example kerosene.

The relative proportions of spreading agent and nitro-body may be widely varied.

\ The hydrocarbon oil ma be present in pro- '\portions (for example rom 1% to 4% by :efiect spreading of the nitro-body over the crystals. The minimum amount of spread-.

ing agent depends upon the particular sub- I stances employed but if necessary can readily be determined by experiment in any particular case. On the other hand the hydrocarbon spreading agent may be present in excess of the minimum quantity required to cause spreading, and-as spreading agents are themselves effective fuels the only limit to the quantity of them which should be employed depends u n the amount of mtro body which is required to give the desired de-- gree of detonability.

A desensitizing 011, such for example as castor oil, may be incorporated with the charge for the purpose of reducing the sensitiveness 85 weight of .the nitro-body)- suflicient only to ofrthe explosive to friction. Instances of I other desensitizing oils are linseed oil, liquid paraflin, wool-fat known as lanoline and heavy oil generally.

I Moreover a cooling a entmay be incororated in e charge if esired with'the'ob- ]ect of reducing the temperature of the gase- 1 g ous products of combustion. Examples of such agents are the nitrates, oxalates and chlorides of sodium, potassium and ammonium, but it is necessary that no ammonium salts be used in charges containing chlorates.

The following examples illustrate the Various explosives manufactured in accordance with the invention Example I.

A cartridge prepared as set forth in the specification of United States Patent No. 1,543,? 98, and containing potassium chlorate as the oxygen-containing salt, is partially immersed in a bath of nitro-benzene, castor oil and kerosene, the nitro-benzene and kerosene being intimately admixed. The nitro-benzene and kerosene are preferably present in the bath in the amounts in which they are intended to be present in the impregnated cartridge, and, according to this example, the amounts of nitro-benzene, castor oil and kerosene are equivalent, in weight, respectively, to about 10%, 1%: and 1% of the impregnated contents of the cartridge.

Example I].

A quantity of dinitrotoluene is dissolved in an equal quantity of mononitrotoluene and some castor oil is dissolved therein and a cartridge containing potassium chlorate crystals is partially immersed in the resulting liquid bath. The nitro-bodies are each present in the bath in a quantity equivalent to l of the finally impregnated contents of the cartridge and the castor oil in a proportion equivalent to 1% thereof. When the nitrobodies have been completely absorbed by the crystals, the cartridge is partially immersed in a bath of kerosene, the kerosene being present in a quantity equivalent to 3% of the finally impregnated contents of the cartridge.

The kerosene, by capillary action, soaks up into the cartridge and carries the previously absorbed nitro-bodies along with it throughout the entire mass of the chlorate crystals and, at the same time, deposits itself in intimate association with the nitro-bodies, uniformly throughout the cartridge.

Emample III.

A further example again comprises 20- Example IV.

An example of a suitable fuel, for impregnation into a potassium chlorate charge, consists of 40 parts of xylene, 40 parts trinitroxylene, 15 parts of kerosene and 5 parts of castor oil, the proportions being by weight in each instance.

Ewa/mple V.

Example V l.

Fuel oil e. g. crude mineral oil or petroleum. preferably having an asphaltic base, may be employed as the hydrocarbon instead of kerosene. According to a further example, the fuel may comprise 69 parts of mononitrobenzene, 17 parts of fuel oil and 14 parts castor oil.

Examples VII, v11! anal lX.

When mononitrotoluene is the nitro-body employed, and castor oil is not required, the fuel may comprise 99 parts of the nitro-body and 1 part of kerosene. In the case of the fuel consisting of equal parts of dinitrotoluene and mononitrotoluene, not less than 3 parts of kerosene should be employed to every 97 of the nitro-bodies. The same minimum proportion of kerosene should be employed when the fuel consists of equal proportions of dinitroxylene and mononitrotoluene.

It may be necessary with certain fuel mixtures slightly to raise the tem erature in order to provide a sufliciently iquid bath for impregnation. I

Various tri-nitro bodies, e. g. trinitroxylene, trinitrotoluene, trinitrobenzene and picric acid may be employed when dissolved in suitable solvents.

1. In a process for impregnatin explosive cartridges of the kind described with a liquid nitro-body, effecting the impregnation of'the cartridge b the aid of a liquid spreading agent, whic agent has the property of assisting the nitro-body to creep over the surfaces of the crystals and thereby to become evenly disseminated throughout the mass 01 said crystals.

2. In a process for the manufacture of explosives of the kind described, the step of uniformly impregnating a charge of crystals by bringing them in cartridge form into contact with a mixture of a nit-ro-body and a spreading agent miscible therewith.

3. In a process for the manufacture of exand a spreading agent.

5. A process for the manufacture of explosives comprisin a crystalline salt containing readily availab e oxy en and a fuel containing a liquid nitro-bo wherein the crystals are first packed to a'high density and thereafter the nitro-body is introduced into the cartridges by the aid of a liquid spreadingagent which is capable "6f asslsting the nitrobod to creep into the fine capillarypassages of t e cartridge.

6. In a process for the manufacture of explosives of the kind described, the step of impregnating a charge of crystals incartridge form by bringing into contactwith them a mixture of a liquefied but normally solid nitro-body and a spreading agent.

7. In a process for the manufacture of explosives of the kind described, the step of imregnating a charge'of crystals in cartridge form by bringmg into contact with them a mixture of a liquefied tri-nitro-body' and a spreading agent.

8. In a process for the manufacture of explosives of the kind described, the step of impregnating a charge of crystals in cartridge form by bringing into contact with them a mixture of lique ed tri-nitro toluene 9. An explosive cartridge of the kind described consisting of a body of crystals ha'ving uniformly disseminated throughout their mass'a mixture of a'liquid nitro-bod and a spreading agent which is a hydrocar on oil.

' 10. An explosive cartridge of the kind de scribed wherein the impregnating fuel is uniformly disseminated throughout and comprises a mixture having as its essential con stituents a nitro-derivative of an aromatic body and a spreading agent. a I 11. 'An explosive cartridge of the kind described wherein the impregnating fuel is uniformly disseminated throughout and comprises a mixture having as its essential constituents a nitro-derivative; of an aromatic body and kerosene.

12. An explosive cartridge of the kind de scribed wherein the impregnating fuel comprises a mixture having as its essential constituents a 'nitro derivative ofan aromatic body and kerosene the amount of kerosene, 4% of the weight of the'nitroexceeding der1vat1ve.

13. An explosive cartridge of the kind de-- scribed consisting of a bod of crystals having uniformly disseminate throughout their mass a mixture of a liquid nitro-body, a

.oil and castor oil.

. 14. An explosive cartridge of the kind described consisting of a body of crystals having uniformly disseminated throughout their mass a ure of a liquid nitro-bod kerosene which forms a spreading agent t erefor, and castor oil. v

' In testimony whereof :I have signed my name to this specification.

' ALEXANDER CRUICKSHANK SCOTT.

spreading agent consisting of a hydrocarbon" 

